Genetic testing in autoinflammatory diseases - past, current and future perspectives.

INTRODUCTION: Autoinflammatory diseases (AID) are a group of rare monogenic illnesses, leading to uncontrolled activation of the innate immune system and presenting with recurrent flares of systemic and localized inflammation. Diagnosis is confirmed by the detection of a class IV or class V gene variant in an AID-related gene and improvements in sequencing techniques have enabled the discovery of new entities. The aim of our study is to explore the diagnostic yield of evolving genetic testing methods for AID and to determine whether increasing gene panels generate a higher diagnostic rate. METHODS: Retrospective study of 2620 patients that underwent sequencing for a clinical suspicion of AID in Belgium, between January 2015 and December 2020. Sequencing was performed through a 10-gene panel between 2015 and 2017, a 25-gene panel between 2018 and 2020 and mendeliome technology with a 66- and a 502- in silico gene panel in 2020. RESULTS: The rate of genetic diagnoses increased along with the expansion of the gene panel with a diagnostic yield of 15% with 10 genes, 16% with 25 genes and 23% with 502 genes. CONCLUSION: Our study is the first nationwide study for autoinflammatory genetic testing and the first use of mendeliome technology for AID diagnosis. Although we confirmed that the bigger the gene panel, the higher the diagnostic rate, this technology generated inevitably a higher financial and human cost although the majority of diagnoses remained amongst the four original hereditary recurrent fevers (HRFs).

Acute Paraparesis after Epidural Corticosteroid Injection Revealing Spinal Dural Arteriovenous Fistula in a HIV Patient.

Spinal dural arteriovenous fistulas (SDAVFs) are often misdiagnosed as their symptoms are non-specific, leading to treatment delay and a poor outcome. We describe the case of a 53-year-old man with a history of progressive paraparesis that worsened abruptly after an epidural corticosteroid injection. We highlight here the need for high diagnostic suspicion for an SDAVF in patients deteriorating after an epidural injection and an indication of repeated spine imaging in such cases. Finally, this is the first reported case of an SDAVF in a HIV-positive patient and it emphasizes the need for a broad differential diagnosis. LEARNING POINTS: Consider an SDAVF in cases of slowly progressive paraparesis and hypoaesthesia, especially if symptoms worsen after an epidural injection.The need for an in-depth work-up including repeated angiographic explorations in cases where no malformation is found in a straightforward manner.In a patient infected with HIV, even though a broad range of neuromuscular diseases can be suspected, non-related aetiologies should not be forgotten.

Visual loss in giant cell arteritis 3 weeks after steroid initiation.

Giant cell arteritis (GCA) is the most common vasculitis in adults and blindness is a common complication if left untreated. Oral glucocorticoids are the mainstay of treatment and if started promptly, loss of vision can usually be prevented. We present the case of a 77-year-old man who developed irreversible bilateral blindness after a confirmed diagnosis of GCA and oral steroid treatment. The roles of diagnostic delay, steroid dosing, significance of visual symptoms at diagnosis and after commencing oral glucocorticoids, and interpretation of ophthalmological signs are reviewed.